What instrument is utilized in celestial navigation to measure angles?

The instrument used in celestial navigation to measure angles is the sextant. This tool is specifically designed to measure the angle between an astronomical object and the horizon, allowing navigators to determine their latitude and longitude. The sextant operates based on the principle of triangulation and can accurately measure angles up to 120 degrees.

While the astrolabe is also a historical device used for navigation, it is primarily for calculating the positions of stars and planets rather than for directly measuring angles in the manner that a sextant does. The compass serves a different purpose by providing directional information relative to magnetic north, and a gyroscope is used for maintaining orientation and stability, especially in aviation and marine applications, but it is not used for measuring celestial angles. Therefore, the sextant stands out as the specialized instrument for this particular function in celestial navigation.